Holybro Pixhawk 4 GPS Module / QGroundControl Arm/Disarm

Hey Guys

So I am having difficulty arming my drone. I have calibrated and connected everything required but on qgroundcontrol is remains as disarmed and doesn’t allow me to click it.

Also on the GPS module it keeps flahsing red on the switch light and had a blue flashing on the gps light.

Can anyone help me arm the quadcopter?

Many thanks,